He et al.: Dysmicoccus brevipes Populations Introduced into Mainland China 183 MITOCHONDRIAL COI FROM DYSMICOCCUS BREVIPES (HEMIPTERA: PSEUDOCOCCIDAE) SUGGESTS CRYPTIC LINEAGE AND PINPOINTS THE SOURCE OF THE INTRODUCTION TO CHINA YAN BIAO HE1,2,*, XUAN WU WAN1, YIN HONG LIU1,*, GUANG MING SUN2, AND RU LIN ZHAN2 1Chongqing Key Laboratory of Entomology and Insect Control Engineering, College of Plant Protection, Southwest University, Chongqing, the People’s Republic of China 2South Subtropical Crops Research Institute, Chinese Academy of Tropical Agricultural Sciences, Zhanjiang, the People’s Republic of China *Corresponding author; E-mail:
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[email protected] ABSTRACT The pink pineapple mealybug, Dysmicoccus brevipes (Cockerell) (Hemiptera: Pseudococci- dae), is a widespread plant-sucking insect of considerable concern because it transmits the pineapple mealybug wilt-associated virus. The purpose of this study was to use molecular methods to clarify the relationship among pink pineapple mealybugs from China, Philip- pines, Thailand and Hawaii, in an effort to determine the geographic origin of the introduc- tion to China. Pink pineapple mealybug samples were collected from 10 counties of 5 prov- inces in China, and samples from Hawaii were obtained. Parts of the mitochondrial genes for cytochrome oxidase I (COI) were sequenced for each sample, homologous DNA sequences of samples from the Philippines and Thailand were downloaded from GenBank. Three hap- lotypes were found in China, 1 from populations of mainland China, and 2 from Hainan island. Phylogenetic analyses suggested that most pink pineapple mealybugs on mainland China probably were closely related to populations in the Republic of the Philippines. How- ever mealybugs from Wanning, Hainan, China, represented a different lineage that clearly diverged from other populations, and which may be of a cryptic lineage or species in the pink pineapple mealybug complex.